Evolution of equine influenza led to canine offshoot which could mix with human influenza

Equine influenza viruses from the early 2000s can easily infect the respiratory tracts of dogs, while those from the 1960s are only barely able to, according to research published ahead of print in the Journal of Virology. The research also suggests that canine and human influenza viruses can mix, and generate new influenza viruses.

Canine influenza is a relatively new disease. The first appearance is believed to be in 2003, as a result of direct transfer of a single equine influenza virus to in a large greyhound training facility and was subsequently carried to many states by the infected greyhound, say the researchers. Similar transfers have occurred among foxhounds in the UK, and in dogs kept near infected horses during a 2007 outbreak in Australia, they report.

In the study, investigators from the United States and the United Kingdom infected dog tracheal explant cultures—essentially pieces of trachea cultured in the laboratory to mimic the cellular complexity and the host physiology of the host—with canine influenza virus, equine influenza virus, and human . (The use of explants has increased in recent years, and they have been shown to be useful for studies of viral pathogenesis.) They then compared the growth of the viruses, and the damage they wrought.

Infection of equine influenza virus from 2003 caused an infection much like that from canine in terms of the virus' rate of replication and the extensive tissue damage it caused. In contrast, viruses from 1963 replicated poorly, and caused relatively minor lesions in comparison with the 2003 virus.

The investigators also transfected cells with DNA containing the genes of both canine and viruses, to determine whether the genes from the two viruses were compatible with each other.

"We showed that the genes are indeed compatible, and we also showed that chimeric viruses carrying human and genes can infect the dog tracheas," says corresponding author Pablo Murcia of the University of Glasgow Centre for Virus Research, UK.

That, he says, means that such chimeric viruses might occur naturally, and would likely be able to infect dogs. These findings have significant implications because they show that dogs might act as "mixing vessels" in which with pandemic potential could emerge.

Studies investigating whether they could infect human lungs are underway.

More information: The manuscript can be found online at jvi.asm.org/content/early/2014… 887-14.full.pdf+html

add to favorites email to friend print save as pdf

Related Stories

Canine influenza was around as early as 1999

Mar 18, 2008

The canine influenza virus, first identified in 2004, had been circulating in the greyhound population for at least five years prior to its discovery and may have been responsible for numerous outbreaks of respiratory disease ...

Recommended for you

Recorded Ebola deaths top 7,000

13 hours ago

The worst Ebola outbreak on record has now killed more than 7,000 people, with many of the latest deaths reported in Sierra Leone, the World Health Organization said as United Nations Secretary-General Ban ...

Liberia holds Senate vote amid Ebola fears (Update)

18 hours ago

Health workers manned polling stations across Liberia on Saturday as voters cast their ballots in a twice-delayed Senate election that has been criticized for its potential to spread the deadly Ebola disease.

Evidence-based recs issued for systemic care in psoriasis

Dec 19, 2014

(HealthDay)—For appropriately selected patients with psoriasis, combining biologics with other systemic treatments, including phototherapy, oral medications, or other biologic, may result in greater efficacy ...

Bacteria in caramel apples kills at least four in US

Dec 19, 2014

A listeria outbreak believed to originate from commercially packaged caramel apples has killed at least four people in the United States and sickened 28 people since November, officials said Friday.

Steroid-based treatment may answer needs of pediatric EoE patients

Dec 19, 2014

A new formulation of oral budesonide suspension, a steroid-based treatment, is safe and effective in treating pediatric patients with eosinophilic esophagitis (EoE), according to a new study in Clinical Gastroenterology and Hepatology, the official clinical practice journal ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.